Platelet-rich plasma (PRP), which contains growth factors for osteoblasts, is clinically used to promote regeneration of osseous tissue. However, we found that human plasma dose-dependently inhibits the growth of cultured MC3T3-E1 osteoblastic cells. In this study, the characteristics of osteoblast inhibiting factor in plasma were investigated. The inhibitory effect on MC3T3-E1 cells was inactivated by pre-heating the plasma. The molecular weight of this factor was estimated to be more than 100-kDaltons by the ultrafiltration method, and the macromolecular fraction strongly inhibited the spreading of MC3T3-E1 cells. Moreover, pre-treatment with a serine protease inhibitor abrogated the inhibitory effect of this factor, suggesting that serine proteases have an important role in inhibiting the growth of MC3T3-E1 cells. These results suggest that the improved preparation of platelets to exclude osteoblast-inhibiting factor from PRP is needed for the efficient regeneration of osseous tissue.
Expression levels of CENP-F mRNA were investigated in 45 surgically resected oral squamous cell carcinomas (OSCC) and 10 samples of normal gingiva, using real time reverse-transcriptase polymerase chain reaction (RT PCR). The relations between CENP-F mRNA and clinicopathologic variables were studied. The mean expression level of CENP-F mRNA was higher in OSCC tissues than in normal gingiva. There was a significant correlation between the expression level of CENP-F mRNA and lymph node metastasis in the cases of OSCC (p=0.024). These results suggest that OSCC with a high expression level of CENP-F mRNA has high metastatic potential.
Ameloblastic fibro-odontoma is an extremely rare odontogenic tumor consisting of odontogenic epithelium, mesenchymal cells, dentine, and enamel. We present a case of congenital ameloblastic fibro-odontoma of the mandible. A 6-month-old male infant was referred to our hospital because of swelling of the mandibular molar region, present since birth. Radiographic examination revealed a well-demarcated radiolucent lesion of the mandible, containing a dental embryo and some small calcified foci. The tumor was surgically resected for a clinical diagnosis of a benign odontogenic tumor. The histologic diagnosis on examination of the surgical specimen was ameloblastic fibro-odontoma. The patient is free from disease 3 years after treatment.
Basal cell adenoma is a rare type of benign salivary gland tumor found most commonly in the parotid gland. We present a case of basal cell adenoma of the minor salivary gland in the upper lip. Histologically, tumor islands were composed of relatively uniform, monotonous cells, and the tumor had a capsule. Immunohistochemically, the tumor cells showed positive immunoreactivity with cytokeratin AE1+3, vimentin, and S-100 protein.
Inflammatory myofibroblastic tumor (IMT) is a spindle cell proliferation with a characteristic fibroinflammatorv appearance. originallv referred to as an inflammatory pseudotumor, plasma cell granuloma, andxanthomatous pseudotumor. We report a case of IMT of the mandible in a 83-year-old woman. The patient had a tumor in the right side of the mandible, measuring 30×30×20mm. Magnetic resonance imaging showed a lesion with high signal intensity on T2-weighted images and homogeneous enhancement. Histological examination of the surgically removed lesion showed that the tumor was composed of loosely arrayed spindle cells in a background of abundant blood vessels and chronic reactive inflammatory cells, including lymphocytes, plasma cells, neutrophils, and eosinophilic leukocytes. The tumor was reactive for vimentin and actin and negative for desmin, S-100, CD31, CD34, keratin, CAM 5.2, EMA, Ki-67, and ALK 1. Because IMT can be confused with other reactive processes as well as with potentially malignant neoplasms, distinguishing these tumors from histologically similar entities plays an important role in assuring appropriate disease management.
The patient was a 51-year-old woman. She was referred to the Department of Respiratory Medicine at our hospital because of a persistent cough. Our department was consulted about a mandibular ameloblastoma in relation to the treatment of her pulmonary lesions. She had suffered from ameloblastoma of the right side of the mandible had undergone enucleation at another hospital in December 1975. Subsequently, a total of 5 operations for ameloblastoma of the mandible were performed over the course of 12 years. Lung metastasis was found in February 2001. In addition, the patient had hypercalcemia probably due to an elevated circulating level of parathyroid hormone-related protein (PTHrP) caused by the metastatic ameloblastoma. We report a rare case of pulmonary metastatic malignant ameloblastoma with hypercalcemia due to PTHrP production.
Concrescence is defined as the fusion of teeth by only cementum. Concrescence of three impacted permanent molars is extremely rare. A 40-year-old man with pain in the right cheek and trismus was introduced to our hospital. In the right side of the maxilla was a partially impacted first molar surrounded by red swelling. Radiographic examination and CT scanning showed completely impacted second and third molars distal to the first molar. The molars adhered to each other and were oriented like a flight of stairs.With the patient under general anesthesia, the teeth were extracted. First, an attempt was made to remove the first molar, but it could not be extracted. With more force, it was extracted with a click. After elevating the first molar, the second and third molars were extracted en bloc. The histopathological diagnosis of the specimen was concrescent teeth. The cementum of the teeth was thickened. and the teeth were fused only by the cementum. without the dentin.
Lymphoepithelial cyst is rarely found in the parotid gland. We report two cases of lymphoepithelial cyst arising in the parotid gland. Case 1. A 34-year-old man had a 2 month history of a gradually enlarging swelling in the left parotid gland. Initial examination revealed a tender, elastic, painless mass in the left parotid gland. Preoperative CT and ultrasonography showed a tumorous lesion between the superficial lobe and the deep lobe of the left parotid gland. The preoperative diagnosis was a benign parotid gland tumor. Case 2. A 61-year-old man had noted a mass in the left parotid gland 2 weeks previously. On initial examination, a firm, elastic, painless mass was present in the anterior position of the left ear. Preoperative MR imaging and ultrasonography showed a cystic lesion in the superficial lobe of the left parotid gland. The preoperative diagnosis was Warthin's tumor or lymphoepithelial cyst. In both patients the lesions were removed surgically, and the histological diagnosis was lymphoepithelial cysts.
Post-traumatic hyperplasia of the mandibular condyle is a relatively rare condition associated with facial asymmetry accompanied by mandibular deviation and malocclusion. We report a case of right condylar hyperplasia that occurred after a traffic-related injury. The patient was a 32-year-old man who presented with asymmetry of the lower part of the face and malocclusion with mandibular deviation to the left. Radiographic examination revealed marked enlargement of the right mandibular condyle. Resection of the lesion was performed, and the remaining portion of the condyle was trimmed and contoured. Postoperative CT scans revealed new bone formation anterior to the condyle. Although there is a risk of recurrence, facial symmetry and good occlusion have been maintained for 4 years after operation.
A patient who had toxic shock syndrome (TSS) after intraoral surgery is described. A 54-year-old woman had pyrexia (40°C), nausea, vomiting, watery diarrhea, and muscle soreness 7 days after surgery for carcinoma of the oral floor. An infection due to methicillin-resistant Staphylococcus aureus (MRSA) developed at the oral wound and progressed rapidly to fulminant septic shock with erythroderma, severe hypotension, and multiple organ dysfunction. The patient received infusion and transfusion therapy, respiratory care, antibiotics, continuous hemodiafiltration, and local irrigation, resulting in a good prognosis. Microbiological examinations revealed that toxic shock syndrome toxin-1 (TSST- 1) was positive in the oral MRSA on the 19th postoperative day. TSS should be considered as a potential complication of oral and maxillofacial surgery.